Fair Value of Financial Instruments - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Percentage of level 3 invested assets in total investment portfolio	9.20%
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Net investment gains (losses) included in net income related to financial assets	$ 5.8	$ 0.1
Net investment (gains) losses included in net income related to financial liabilities	$ 1.9	$ 1.3

Percentage of invested assets in the total investment portfolio in Level 3 carried at fair value on a recurring basis.

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Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

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Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

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